Improvement in piston packing



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JAMES l). MCLEAN, OF` BROOKLYN, NEW YORK. Letters Patent No. 63,071, `elated March 19, 1867..

IMPROVEMENT IN risron'rnome.

To ALL WHOM 1T MAY coNcERN: l .i

Be it known that I, JAMES P. McLEAN, ofthe city of Brooklyn, in the county vof Kings, and State of New York, have invented a new and useful Improvement in Steam or other Packing for Piston-Rods, Cylinders, or Shafting; and I hereby declare the-following to be a full, clear, and exact description thereof, reference being had to the accompanying drawings, which are lettered to correspond with and form apart of the specification.

V'.lo enable those skilled in the manufacture and-use of steam and other packing to construct and use my improvement, I will describe it as follows: v

Figure lis a perspective drawing of a steam cylinder, with piston" P,and rod S, provided with my improved. packing, R C, which improvement consists in combining India rubber, R, and cork, C, in such a ma ner thatthe rubber will actas a follower to the cork when in the stuffing-boxes or piston, thus holding the cork and zinc or lead against the cylinder or rod S. l I am aware that cork and lead are claimed in the application of James P. McLean and John Vandercar for improvements in steam or'other packing, allowed May 15, 1866, and that India rubber has been used for packing purposes, with canvas. and lead, hence they are not claimed as my inventionV in this application when combined as above; but my invention consistseinsthe combination of two elastic `bodies or substances o dierent expa'nJ sive and absorbent properties, so arranged that the absorbent body C will be forced and held against the rod, shaft, or'cylinder, by the more expansive and more Aelastic substance, Indialrubber', R.

I nd, from-a more careful analysis, that the rst introduction of steam into a cylinder (packed with cork alone) will cause a shrinkage of :the packing to take place; hence it becomesnecessary to put in more packing or employ some other means to ll'up the vacuum; consequently the India rubberl or caoutchoucR, is more expansive and retains its expansion, so that it counter-acts the aforesaid shrinkage, and keeps-forcingthe cork C `against-thc cylinder or rod, (when placed behind the cork,) as shown in the accompanying drawings, by

' which means the quirks of the absorbent: C become filled with the leaden particles and lubricating oil, thereby making the packing perfectly ysteam-tight. V In my opinion the cork, when lled'as above, forms' a lubricating packing equal to black lead (after sh'rinkagehas been overcome by the means set forth in the above.)

I secure the rubber R and cork C together byv zinc or leaden strips wound around the saine, as shown at N in the drawings, and for practical purposes I would harden the lead alittle by th'e introduction of ,antimony into its composition preparatory to rolling into sheet lead, from which I cut the strips N N', and when the-zinc strips N N are used in lieu of lead, in combination with the cork C, theywill be found sufficiently hard fo'r'ell ordinary packing purposes, land when forced 'against the pistonrod or cylinder, they become embedded into the packing C, and hold the same into shape A,without canvas or other jackets. I-prepare the cork'C, if necessary, by coating it with a composition of black lead and pulverized soap-stone or tale, or the above muy be used separately for filling up the quirks of the cork, and protecting it (the cork) from burning, as well as 4to facilitate its great lubricating .properties when prepared as above net forth.`

Therefore what I claiml as new and useful, and what I wish to secure by Letters Patenti-of the United States of North. America, is I I Combining the cork.G, rubber R, withv or without the mineral coating, andseouring the same by means of metallic strips, all substantially as described and for the purpose set forth and shown in the drawings.

In testimony whereof I hereunto subscribemy name in the presence of two witnesses.

I JAMES P. McLEAN.

Witnesses JOHN CURTIS, J onN VANDERCAR. 

